{"assessment":{"best_window":{"end":"2026-06-10T00:40Z","end_local":"03:40","hours":4.58,"label":"good","mean_quality":0.93,"start":"2026-06-09T20:05Z","start_local":"23:05"},"cost":{"altitude":0.0,"clouds":0.13,"darkness":3.36,"moon":0.3},"formula":"astronomy = 100 * min(1, sky_hours / reference_hours) * peak_sky; overall = astronomy * score_weather / 100 (null when the weather is unknown)","hard_limit":null,"headline":"Worth it","hourly":[{"alt":null,"cloud":5,"high":0,"iso":"2026-06-09T18:00Z","label":"unusable","low":1,"mid":5,"moon_alt":-44,"precip":0.0,"q":0.0,"rh":83,"sky":"civil twilight","temp":11.0,"time":"21:00","wind":2.7},{"alt":null,"cloud":4,"high":0,"iso":"2026-06-09T19:00Z","label":"poor","low":2,"mid":2,"moon_alt":-39,"precip":0.0,"q":0.14,"rh":81,"sky":"nautical twilight","temp":10.7,"time":"22:00","wind":1.1},{"alt":null,"cloud":2,"high":0,"iso":"2026-06-09T20:00Z","label":"marginal","low":1,"mid":2,"moon_alt":-33,"precip":0.0,"q":0.49,"rh":82,"sky":"astronomical twilight","temp":10.0,"time":"23:00","wind":0.7},{"alt":null,"cloud":2,"high":0,"iso":"2026-06-09T21:00Z","label":"good","low":2,"mid":1,"moon_alt":-24,"precip":0.0,"q":0.98,"rh":83,"sky":"night","temp":9.8,"time":"00:00","wind":1.2},{"alt":null,"cloud":2,"high":0,"iso":"2026-06-09T22:00Z","label":"good","low":2,"mid":0,"moon_alt":-14,"precip":0.0,"q":0.98,"rh":82,"sky":"night","temp":9.7,"time":"01:00","wind":1.3},{"alt":null,"cloud":2,"high":0,"iso":"2026-06-09T23:00Z","label":"good","low":2,"mid":0,"moon_alt":-3,"precip":0.0,"q":0.98,"rh":82,"sky":"night","temp":9.2,"time":"02:00","wind":1.1},{"alt":null,"cloud":2,"high":0,"iso":"2026-06-10T00:00Z","label":"good","low":1,"mid":1,"moon_alt":8,"precip":0.0,"q":0.83,"rh":86,"sky":"night","temp":7.6,"time":"03:00","wind":3.0},{"alt":null,"cloud":1,"high":0,"iso":"2026-06-10T01:00Z","label":"marginal","low":1,"mid":1,"moon_alt":19,"precip":0.0,"q":0.41,"rh":87,"sky":"astronomical twilight","temp":7.3,"time":"04:00","wind":2.8},{"alt":null,"cloud":1,"high":0,"iso":"2026-06-10T02:00Z","label":"poor","low":1,"mid":1,"moon_alt":30,"precip":0.0,"q":0.12,"rh":87,"sky":"nautical twilight","temp":7.1,"time":"05:00","wind":2.4}],"peak_quality":0.98,"peak_sky":1.0,"quality_hours":5.21,"reasons":["daylight and twilight cost 3.4 quality-hours","moonlight cost 0.3 quality-hours"],"reference_hours":4.0,"score":98,"score_astronomy":100,"score_weather":98,"sky_hours":5.34,"verdict":"good","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2026-06-09T18:30Z","end_local":"21:30","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2026-06-09T17:50Z","start_local":"20:50"},{"end":"2026-06-09T19:15Z","end_local":"22:15","hours":0.75,"label":"poor","mean_quality":0.14,"start":"2026-06-09T18:30Z","start_local":"21:30"},{"end":"2026-06-09T20:05Z","end_local":"23:05","hours":0.83,"label":"marginal","mean_quality":0.48,"start":"2026-06-09T19:15Z","start_local":"22:15"},{"end":"2026-06-10T00:40Z","end_local":"03:40","hours":4.58,"label":"good","mean_quality":0.93,"start":"2026-06-09T20:05Z","start_local":"23:05"},{"end":"2026-06-10T01:30Z","end_local":"04:30","hours":0.83,"label":"marginal","mean_quality":0.4,"start":"2026-06-10T00:40Z","start_local":"03:40"},{"end":"2026-06-10T02:15Z","end_local":"05:15","hours":0.75,"label":"poor","mean_quality":0.12,"start":"2026-06-10T01:30Z","start_local":"04:30"},{"end":"2026-06-10T02:50Z","end_local":"05:50","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-06-10T02:15Z","start_local":"05:15"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":2,"dark":false,"high":0,"local":"20:00","low":0,"mid":2,"precip":0.0,"rh":84,"temp":12.8,"time":"2026-06-09T17:00Z","wind":3.0},{"cloud":5,"dark":false,"high":0,"local":"21:00","low":1,"mid":5,"precip":0.0,"rh":83,"temp":11.0,"time":"2026-06-09T18:00Z","wind":2.7},{"cloud":4,"dark":false,"high":0,"local":"22:00","low":2,"mid":2,"precip":0.0,"rh":81,"temp":10.7,"time":"2026-06-09T19:00Z","wind":1.1},{"cloud":2,"dark":false,"high":0,"local":"23:00","low":1,"mid":2,"precip":0.0,"rh":82,"temp":10.0,"time":"2026-06-09T20:00Z","wind":0.7},{"cloud":2,"dark":true,"high":0,"local":"00:00","low":2,"mid":1,"precip":0.0,"rh":83,"temp":9.8,"time":"2026-06-09T21:00Z","wind":1.2},{"cloud":2,"dark":true,"high":0,"local":"01:00","low":2,"mid":0,"precip":0.0,"rh":82,"temp":9.7,"time":"2026-06-09T22:00Z","wind":1.3},{"cloud":2,"dark":true,"high":0,"local":"02:00","low":2,"mid":0,"precip":0.0,"rh":82,"temp":9.2,"time":"2026-06-09T23:00Z","wind":1.1},{"cloud":2,"dark":true,"high":0,"local":"03:00","low":1,"mid":1,"precip":0.0,"rh":86,"temp":7.6,"time":"2026-06-10T00:00Z","wind":3.0},{"cloud":1,"dark":false,"high":0,"local":"04:00","low":1,"mid":1,"precip":0.0,"rh":87,"temp":7.3,"time":"2026-06-10T01:00Z","wind":2.8},{"cloud":1,"dark":false,"high":0,"local":"05:00","low":1,"mid":1,"precip":0.0,"rh":87,"temp":7.1,"time":"2026-06-10T02:00Z","wind":2.4},{"cloud":1,"dark":false,"high":0,"local":"06:00","low":1,"mid":1,"precip":0.0,"rh":87,"temp":7.1,"time":"2026-06-10T03:00Z","wind":1.9}],"forecast_source":"history","forecast_updated_at":"2026-10-12T16:00:42Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-06-09T20:03:41Z","dark_hours":4.56,"dark_to":"2026-06-10T00:37:01Z","moon":{"illumination":0.34,"phase":"waning crescent","waxing":false},"moon_free_dark_hours":3.22,"moonrise":"2026-06-09T23:17:53Z","moonset":"2026-06-09T11:15:30Z","sunrise":"2026-06-10T02:46:18Z","sunset":"2026-06-09T17:54:23Z","twilight":{"astronomical":{"end":"2026-06-09T20:03:41Z","start":"2026-06-10T00:37:01Z"},"civil":{"end":"2026-06-09T18:28:20Z","start":"2026-06-10T02:12:22Z"},"nautical":{"end":"2026-06-09T19:11:49Z","start":"2026-06-10T01:28:53Z"}},"window_end":"2026-06-10T09:00:00Z","window_start":"2026-06-09T09:00:00Z"},"night_date":"2026-06-09","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}